New in Echoview 4.30
for users of data from Simrad echosounders

Note: Simrad is a subsidiary of Kongsberg. See also New for users of Kongsberg echosounders

This page summarizes the new features, improvements and other changes that have been implemented in Echoview 4.30 which specifically affect the use of data from Simrad echosounders.

TVG range correction bug in Echoview 4.20

It has come to our attention that Echoview was incorrectly setting a default parameter value in Echoview 4.20. The affected setting was the Apply TVG range correction setting on the Calibration page of Variable Properties dialog box for TS raw variables derived from Simrad Ex60 raw data in new EV files only. This bug has been fixed in the latest web download of Echoview 4.20 and in Echoview 4.30. We apologize for any inconvenience that this bug may have caused.

When EV files were created in Echoview 4.20, the TVG range correction offset was being set to a value of 2 by default. The correct value for this setting under most circumstances is 0. However if inheritance of virtual variable properties was in use (which also occurs by default) then TS data values would be re-corrected by the specified amount in the relevant single target variable.

If you use raw data from a Simrad Ex60 echosounder, and if you created new EV files in Echoview 4.20, and if within those EV files you used raw TS data to generate single target echograms, we recommend that you check the TVG range correction offset settings to ensure that either:

• The TVG range correction offset on the Calibration 2 page of the Variable Properties dialog box for the TS raw variable is set to 0 if you are using the Single target detection - single/split beam (method 2) operator, and that the value of the TVG range correction offset setting on the Calibration page of the properties for your single target variable is also set to 0.
• Note: If both of these settings were 2, then there would be no effect of this bug on your data. There is only a problem if those two settings are different, which is highly unlikely based on the circumstances outlined above.

- OR-

• The TVG range correction offset on the Calibration 2 page of the Variable Properties dialog box for the TS raw variable is set to 2 if you are using the Single target detection - single/split beam (method 1) operator or the Single target detection - dual beam (method 1) operator.

See also: New features in Echoview 4.30 for a description of changes that may affect you but are not specific to data from Simrad echosounders.